Research Of The Real-time Transportation Of Network Video Monitor System Based On MPEG-4

In recent years, with the rapid development of Internet, video codes and hardware technology, the network video monitor system developed rapidly. The real-time transportation of MPEG-4 video is very essential in the network video monitor system; it is crucial for the robustness and stability of the system. Video real-time transportation typically has delay and loss requirements, which cannot be adequately supported by the current Internet. A dominant portion of today's Internet traffic is TCP-based. Therefore, designing a TCP-friendly congestion control mechanism suitable for transporting MPEG-4 video becomes important.The thesis first summarizes MPEG-4 video coding standard and its features, analyses the compression algorithm of MPEG-4 video, describes Real-time Transport Protocol and RTP Control Protocol. Then the thesis chooses appropriate transport scheme based on the features of network video monitor system, and designs the transport network.For the RTP packetization strategy, the thesis analyses the packetization algorithm that regards VOP as the unit, and gives an improvement. For reducing the packet numbers in maxnum and giving attention to the Real-time character of monitor system, the thesis adopts the strategy that one packet loads several VOPs. For reducing the packets-lost influence to the decode quality on receiver, the thesis put forward the interleaving packetization strategy. Then the thesis depicts the packetization algorithm and designs the payload type. The experiments indicate that the improved packetization algorithm has been reduced the quantity of the RTP payload.The author analyzes feedback congestion control algorithm suited to MPEG-4 video. Taking into account the matching transport rate and bandwidth, the author gives an improvement and optimization of the feedback congestion control algorithm. For reducing vibration produced by congestion control, the thesis put forward the steady increasing factor strategy. Then the thesis depicts the improved congestion control algorithm. The experiments indicate that theimproved congestion control algorithm has more effective on lower vibration.Finally, the thesis summarizes our work, points out the weak point and the research direction in future.